.g-main {
    position: relative;
    height: 400px;
    background: #eaedf3;
}
.g-head {
     box-sizing: border-box;
     height: 60px;
     background: #22354a;
     padding: 13px 30px;
     font-size: 18px;
     color: #fff;
 }

.g-body {
    position: absolute;
    left: 180px;
    top: 60px;
    bottom: 0;
    right: 0;
    padding: 10px 13px;
}

.menu {    position: absolute;  z-index: 99;  right: 10px;  top: 4px;}
.menu .m-menu .m-subMenu  {padding-right: 20px;}